NuPower
TM
LS75T01 User Manual
Rev -
3
SETUP AND OPERATION
This section provides specific details for proper operation of the NuPower LS75T01 module. Following
these guidelines will prevent damage to the power amplifier or external equipment.
3.1
POWER SUPPLY REQUIREMENTS
To operate the NuPower LS75T01, ensure that the power supply has adequate overhead to source the
current demand of the RF power amplifier. The power supply source must provide a typical voltage of
+28 VDC with greater than 10 amps capability.
3.2
CONNECTING A PROPER LOAD TO THE ANTENNA TERMINAL
To prevent damage to the PA, the antenna terminal must be terminated into a 50
Ω
load. Examples of a
proper load include:
•
Directly connecting to an antenna specified for the frequency range (800 MHz to 2500 MHz).
Connecting to an inappropriate antenna may result in damage to the PA module.
•
Connecting to a proper antenna through a 50
Ω
transmission line or coaxial cable. Avoid using
damaged cables or corroded connectors while attaching the unit to an antenna.
•
Terminating the antenna terminal into a 50
Ω
power attenuator with minimum 20 dB
attenuation.
•
Connecting to a load capable of dissipating the RF power from the PA module. Loads capable of
handling >125 Watts (min) are recommended.
3.3
POWERING-UP THE NUPOWER LS75T01
The NuPower LS75T01 must be terminated to a proper load before power is applied. Refer to Section
3.2 for the specifications of the proper load. After the PA is properly terminated, the interface cable can
be connected to the unit and power can be applied. The PA is now ready for operation.
3.4
TRANSMIT TURN-ON TIME
Caution: Do not apply transmit data until the PA module is at full power. This will prevent
loss of data at the beginning of a message.
The NuPower LS75T01 is at full power approximately 1 µS after the RF Enable line goes low (ground).
Therefore, transmit data can be applied to the input after 1 µS without loss of data.
3.5
RF OUTPUT POWER VS. SUPPLY VOLTAGE
The NuPower LS75T01 was designed for +28 VDC operation.
